This pipette allows the transfer of very small volume proportions of liquids, ranging from 0.1 ml to 50 ml. It is designed in different sizes, to be used according to the manipulator’s need. However, some bibliographies state that they are ideal for transferring volumes between 5 ml and 25 ml.
This is so because transfers smaller than 5 ml should ideally be handled by Gilson-type pipettes, and for larger transfers burettes should be used.
Features of the serological pipette
They are part of the blow out pipettes
Serological pipettes have the characteristic of being considered within the group of blowing or blow out pipettes . A blowing pipette is one in which the capacity described on its surface does not take into consideration that a part of the liquid adheres to its walls after pouring it into the container.
This liquid is part of the volume to be dispensed. Therefore, in order to obtain the entire volume described, the pipette must be blown to expel that remaining liquid and obtain the precise amount indicated by the pipette in the receiving container.
Open top end
To expel the liquid, these pipettes have their upper end open, their structure resembling a straw. Through this hole the manipulator can create a vacuum by placing his finger and thus keep the liquid inside the pipette.
In the same way, after pouring the contents of the pipette into the receiving container, it is possible to blow on the open end to pour the last drops of liquid adhering to the walls of the pipette, to ensure pouring the entire volume indicated by the pipette. .
This type of pipette is identified by a frosted belt near its upper end or by two thin colored rings around the neck of the pipette.
Recommended filling with a pipette
Although some serological pipettes are blown, the use of a propipette for filling is suggested. This is because, due to the very small quantities it carries, it is difficult for the user to control the sucked liquid when carried out with the mouth.
Uses of the serological pipette
To transfer volumes of body fluids
As its name indicates, it is the pipette used for the transfer of volumes of fluids from body fluids, for the study of pathogens and antibodies, among other elements.
Because the serological pipette can be used for the transfer and measurement of liquids with potentially pathological gases for the technician or the environment, they bring with them a small filter to prevent pathogens from coming into contact with the atmosphere .
In the food and cosmetic industry
It is also frequently used in food production and in the cosmetic industry. It is used when the volumes to be transferred are very small, and it is recommended to use the smallest possible scale to avoid errors in the required volume.
For example, if it is necessary to transfer 0.9 ml, the use of a 1 ml pipet is recommended instead of a 10 ml pipet.
Differences between serological pipet and volumetric pipet
The main difference is that the serological pipette is a graduated pipette that allows transfer of various volumes of liquids with the same pipette as required. In contrast, the volumetric pipette only allows you to measure a single volume.
This feature makes the volumetric pipette much more accurate and precise than the serological pipette.
The serological pipette is marked so that some can be blown or blow out . That is, after pouring the liquid it must be blown through the upper end to see the rest of the liquid adhering to the walls.
However, no volumetric pipette allows post-blowing. Whether pouring or holding pipettes, the capacity described on the surface of the pipette should be considered by the technician who selected the pipette.